Carburetor



Feb- 9 1926' C. l.. RAYFlr-:LD

,CARBURETOR Filed April 30, 1920 4 sheets-sheet 2 Feb 9 1926.

CARBURETOR Filed April 30, ,1920

C, L. RAYFIELD v4 Sheets-Sheet 3 Feb. 9 1926.

C. l.. RAYFIELD CARBURETOR I Filed lApri 1 5o, 1920 4 sheets-'sheet 4 l" VJ Patented Feb. 9, 1926.

illlillTEl) STATES PATENT FFICE.,A

enemies 1:.. nAvrmLn, or CHICAGO, 1LLrNoIs, .AssIeNon To BENEKE MANUFACTUR- rue' CorrPANY, or CHICAGO, ILLINors, A

CoRrouA'rIN or ILLINOIS.

ennsunnfron.

Application med prix so, 1920. serial No. 377523.

To all Wiliam it may/concern Be it known that I, CHARLES L. RAYFIELD,

a citizen of the United States, and a resident ot' the city of Chicago, Iin the county of Cook and State of Illinois, have invented certain new and useful Improvements in Carburetors; and l do hereby declare that the following is a. full, clear, and exact description of the same, reference being had to` the accompanying drawings, and to the numerals of reference markedthereon, which form a part of this specification.

This invention 'relates to a plain tube quired certain adjustments which it was not Within the ability make.

It .is one of the principal objects, thereiiore, of this invention to provide an irnproved plain tube' carburetor Jfor vinternal combustion engines of such construction that the mixture of hydrocarbon fuel passing therethrough is automatically varied to be adapted to varying speed and load conditions oi the engine.

@ther and, vfurther important objects of this invention will he apparent from the disclosures in the speciiication and the accompanying dralwings.

The invention' (in a preferred form) is illustrated in the drawings and hereinafter more fully described.

iin the drawings:

Figure .i is a top plan View of a carn huretor embodying the principles of this invent-ion showing a part of the air inlet thereof" in section.

Figure 2 is a section ou line 'f2-J2 ot Figure 1 'with parts in elevation.

Figur il is a view in elevation of. the gas outlet end of the carburetor.

Figure 4 is a :section onv line Li-*ei of Figure l. with parts omitted and with parts 'n in elevation. i

5 is a section ou line 5--5 of of the ordinary user to Figure 6 is a section ,on line 6-6 of Figure 5. v

Figure 7 is a section on lin-e 7`7 of Figure 3 with parts in elevation.-

Figure 8 is an enlarged fragmentary dctail section showing the main inlet nozzle.

Figure 9 is an enlarged fragmentary detail section of the auxiliary nozzle.

Figure 10 is an enlarged fragmentary section on' line 10--10 of Figure 1.

Figure 11 is an enlarged fragmentary section on line 11--11 of Figure 10.

As shown on the drawing:

The carburetor comprises in general the cast casings 1 and 2,V which are secured together at 3, as clearly shown in Figure 2. The casing 2 is provided at one end with a ange 4, which is `adapted to be secured to t e intake manifold of an internal combustion engine and at the opposite end with a flange 5, to which the air inlet casing 6 is secured by means of the machinescrews 7. A tloat chamber 8 is rovided inside the casing 1 and an apertured internally threaded boss y9 is formed on the lower portion osaid casino'. For closing the outer end of the aperture in the boss 9 a threaded plug 10 having a hexagonal head 11 is inserted therein. Al centrally apertured plug 12 having a passage 13 therein is engaged in the inner end of the aperture in the boss 9. ln order to introduce liquid fuel into the chamber b, an annular casting 14C is eugaged around' the internally apertured boss i ,9 between the bottom of the casing l and the hexagonal head 1l of the plug 10., In this way an annular chamber v15J is 4provided which is in communication with the aper- -'ture in the boss 9, through suitable openings 15a iu said boss lust above the top of the plug 10 therein. Said casting 14 is provided with an integral centrally apertured externally threaded boss 16 whereby it, may be connected 'with a fuel supply tube. A screen 17 engaged around the boss 9 inside the chamber 15 to prevent dirt or Jforeign matter from entering the carburetor.

AF or closing the float chamber, the cover plate 18 is removably secured on the casing l' byiuachine screws 19 and beneath and secured to said cover plate 18 is an annular plate Q0, which engages the inner periphery of the upper portion of the casing 1, as shown' in "figure 2. Secured in a central 'nio audaces tral aperture therein and extends upwardly through the sleeve 58 into the chainbe'r 32, as clearly shown in Figures tand 8. Bleeder apertures 61 and 62 are provided in the upper portion of said tube and in the `lower portion thereof a passage 63 is provided communicatingwith the chamber 57. The lower end of the aperture inthe lug 59 is threaded and the centrally recessed) threaded lug 64 is engaged Ain said threaded portion. .Supported in the central recess in said plug 64 and extending upwardly inside the tube 60 is a tube 65, which Vis provided with an aperture 66 .communicating with the aperture 63 in the tube 60. A peripher; recess 67 in the plug 64 communicates with the central recess therein and with the interior of the tube 65. An annular casing 68 is engaged around said annular' recess 67 and provides communication between said recess and a vertical air tube 69, which is secured in said casing, and is provided with an aperture 69. By this constrution atmospheric pressure from the tube 69l is on the interior of the tube and passages communicating therewith. `As shownv in Figure 10, a passage 7 0 is cored in the casing 1 and provides communication between the float chamber S and the chaniber 57 surrounding the main inlet now/ile. For controlling the flow ot liquid fuel through the passage 70, a needle valve 71, which is rotatably supported in the casing 1, is engaged in "he communicating passage. between the fioat chamber 8 and the passage 7. Said needle valve 71 is secured in a threaded sleeve 72, .which is engaged in a threaded aperture in the casing l and which is provided with a vertically grooved portion 73 which is enfraged by a spring pressed datent (not shown for locking it in adjusted posiiion. A knurled head 74 is provided in the sleeve 72 fo.; rotatingthe same to adjust the position of the needle valve 7l.

The casing 6 provides means for connecting the air chamber 3l with a source ot warm air supply. The boss 75 on saidV casing 6 is adapted to receive a pipe leading from a source of warm air supply andthe set screw 76 acts-to secure said pipe 1n the boss 76. Said casing 6 is also provided with' a flange 77 having apertures therein which register with the apertures in the .lange 5 on the. casing 2, and through 'which the inachine screws 7 are engaged to secure the casing 6 to the casing 2. Adjacent the ange 77 opposite portions of the casing 6 are cut -away to provide openings therein.

openings are normally closed bv plates 7 Said which are engaged thcieover inside the caring 6. Said plates 78 are supported on' the outer ends of the forked portion-.otthe ther-` inostatic element 7 9, which is secured to the inner side of the end of the casing 6 by the u bolt 8O engaged therethrough. For securing always exerted the thermostat-ie element 7 9 securely in posi tion inthe casing, a nut 8l is engaged on the inner end of the bolt 80. The thermostatic element T9 is composed of two adjacent oontinuous strips of metal of dilierent expansibility so that when said metals are heated the relatively diderent expansion thereof will cause the plate covering the openings in the casing 6 to be moved inwardly and thus allow cool air to enter the casing 6 and the air chamber 3l communicating therewith.

rlhe operation is as follows:

Liquid hydrocarbon fuel is intri-duced into the ioat chamber 8 through the apertured boss 16 in the casing 14 and the constant level of fuel in said float chamber is maintained by the action of the float 25 and` the valve 23 connected thereto in a manner which is well known in the art. 23 may be adjusted longitudinally by ro- Said valve tating the threaded portion 24 thereoi2 in the internally threaded sleeve 22.

When the motor isrunning idle .the apertured plug 54e in the idling nozzle 52 is the only source of fuel supply in action. Agir is supplied to the. jet from said plug through the passage 46, and the amount of air passy ing therethrough may be regulated by means s ot the screw passing through said passage 46 may creased or weakening the mixture tor when running idle. Liquid tuel is supplied to the nozzle 52 through the passage 5G.v which leads directlv to the chamber 8.

Closing the air inlet or choke valve 34 closes the entrance to the passage 46 and also to thc air inlet chamber 3l. This is accomplished manually by the operation of the lever 43 from the front ot the engine or of the lever 42 from the rear thereof. lf

supplied to the modesired said lever i2 may be secured. in

anyadiusted position desired and the lever 43 used tor operating the choke or air inlet valve 34 Awhen starting the engine.

The supply of fuel for idling enters the gas outlet ahead of the throttle valve 35, around a passage 36 in the stem. thereof, and through the passage 47. Sutli'cient fuel will be supplied through said passage to idle the engine when throttle valve is entirely closed. v

rlzhe main nozzle s vstein is Filled through the aperture 63 to a level equal to the level 49, whereby the amount of air' diminished, thus strengthening 'orl of the fuel in the iioat chamber. the iior- Y inal level being. shown by dotted lines in Figures 2, 4 and S.- The air pressure through the aperture 69n4 in the upper end of the air inlet tube 69 forces fuel through the main nozzle which is formed between vthe tube 60 and the sleeve 58 surrounding said tube. As soon as Vthe liquid 'fuel is exhausted from the air supply tube 69, air is fed through .the aperture 69 therein iso vilain inlel nozzle nys air ia liisl; lfilcd iliroiiig'h the air lili-Heiler iiiirliro (il and al; higher speed is lilefl iliifoii lli lha lili-.ieder anorl'ure due lo ilie .lowering ol lzhe liicl lorill, llius supilly' L, a, @rigor 'iniirtui'c lor the speed at which llio engine is operating. ,llt liigh animals aildilional fuel isi iuliroduend into the iiiiiilni'e fioiii ihc high speed aperture 53 and ihn idlingli; lulio said l'iiel lining drawn llii'oulg'li saisi high speed aperture duo lo lhe faouuiu produced when the en- "i ...i is running; ali high speed. 'lfhis operA a on dan iio the ilacl that Willi said lzuho lil? loci 'Eril lo one z 'iin ol? the narroiiiesil. point l'lui riinluii 13553 l c sialic force exerted by ed suction al hin-li. speed will lie iln il, ihn iltriiaiiiic :lo'rce ezicried by ...on1 olf air agaiiisl` the aperlure 53, it liiiilorsfliood that lhc Venturi. widens 'iiiii llicrelilirough devreises pio li," and ai: tiyisifaloi into than the lu nucl. fi. or ,loin-speed lube 52 is al* L inneel'ed lo llic iloal; chainliery and. illus. i noon iis iliv niol'or is sluit down, in :iii iilliingi; alicell, 'there iiloiiliy of l o lli:

doriiiiii;

4'lflie illlliiir .warn iliioc -if $1,715 iii'ailiilile lo id lix lli@ inoi'or.

provides a the iiiixtiiie rllills iiiifijinl'ioi'i, lLliiirelioifo. lilaiii lull-i ciii'liiii'iiifiir wherein iii auioiiiuliually rariillil lo Huilf the engine sliced, and iii which llos rari-alion"olE iiiircy l'iirii is: :ieriiiiiplisliell ii'illioul: lho use oli iiioriilile iiilvoefi. 'llie 'Jullie ol the automat-ie :ii'liusli'iieiilri olf 'his (-ai-liiirolor is enhanced lili llio iiioiiifiii'i ol :i llieriiiosialirallv i'oiiii'olloil xiii' iiili:I llio ali .iiilol (i ifi oon* nim-loll willi #Mirco ili nai-iii air Supply i, ich i\i'ii'oi-1 Lilo carlitii'oloi. ll llio ziii' i'w lila-#lilo iifxiiwlroly u'ai'iii [lio arlioii llioi'iiiirrilailii: nlciiiiiil if) will vor plaie "ill lo lio ili'ziwii inunil lliiiiA :iiloii' cool air io oiilir llic "l. .lli l li :,iicofl lilro suction ol' i lia-Siu' lliii i mi in iii spring zillion olt the -iiii Til and aildiiional cool l. io lilio eiigi'iuo. ildjiislol liquid l'ucl supplied cui through the paS- lloal iliainlicr bl may lie lo; rolxiiiiigi `ie nei-ille 'valve 7l. and or dei: the size ol. the u the loal cliaiiilier l and "l'liii ralliiirol'ir yriiriilnil lig.' llii invention is iii- 1s ly ol the ,vilain itu` or rigid andy iliio iro ihn iloi i coni l:anniuw om iassured inflazione at all times and danger of explosions in the lill carburetor due to bacli'l'iring is olivialed.

l ani aware that numerous i'lel'ails of con struction may lie varied ihr/nigh a Wide rang-e Withoul departing from the iii'inciples of this invention, and l. therefore do nolJ iiii'- pose limiting the patent granted otherwise than necessitated by the prior art.

l elaini as my invention:

1. In a carburetor, the combination of :i inain mixing' chamber, ainauxiliary iriiiiing; lo pase-age, a, fuel supply chamber, an i'iilcl; nozzlc communicating with the :lfuel suliiply cliaiuloer and extending inl'o the niaii niiiiing,r chamber, a Second iiilel' nozzle roiiiinuni eating separately with the liicl supply chain ber and opening into the auxiliary mixing),l passage and having an aperture opening into the main mixing eliainlienlor introducing additional liquid 'fuel therein iiiliou a high vacuum is produced.

2. In :i ,carbureior, the. coiiiliinalion with a casing having constant size /niai'iually regulable passages therein, of a nozzle opening into one of said passages, and a second nozzle opening iiilo bolli of said pansagea 295 and conuniinicaing` separately with the 'lliel supply chamber.

Il. ln a carburetor, a fuel ohaiiilicr, a 'niaiii mixing chamber, un aiiiiiliziijyY iiiixing passage, and a plurality oi iluol nozzles conv @il .lor siiiiullaneously culling` oli' i-,i'iiniiiiiiiialion lictueen the nii' inlet aiid bolli Suid iiiixiiig chainhi-r and passage. loll lli-a carburetor, a fuel supply cliaiubei', a iii-ain mixing cliainlier, a luci nozzle therefor, an auxiliary mixingy passage, a, second fuel nozzle coiiiii'iuiiicaiing` sepa ralely with the 'fuel supply chainlioiand ii openingy into said auxiliary mixing pas sage, said latter nozzle haviiiig an opening therein communicating` upstream in said inain mixing chamber.

ln lesliiiiony whereof I have hereunto sulili scribed iuy naine.

CHARLES L. .lillirlflllill 

